Isolation

Isolation in GoMyRobotOS is a contract-level concept: the Partition Contract declares what must not be shared or reachable between partitions. How that declaration is enforced is a property of the target backend (Xen, XNG/XtratuM, hardware WorldGuard, or future mechanisms), which is exactly the layer the contract deliberately ignores.

Isolation dimensions in the contract

Dimension	Contract expression	Notes
Spatial (CPU)	`execution.cpu_set`	a partition sees only its assigned cpus
Temporal	`execution.scheduling`, `execution.timing_budget`	static allocation / bounded budget, not best-effort sharing
Memory	`memory.regions` with name, size, permissions	partitions do not address each other’s regions
DMA	`dma.permitted_regions`	DMA may only touch declared regions
Interrupts	`interrupts.owned`	an interrupt belongs to exactly one partition
Devices	`devices.ownership`	device access is declared, not discovered
Communication	`communication.endpoints` (size + rate bounds)	everything cross-partition goes through declared, bounded channels
Trust	`partition.trust_domain`, `partition.criticality`	drives how strictly the backend must enforce the above

Field definitions: Contract specification.

What GoMyRobotOS specifies vs. what a backend realizes

GoMyRobotOS creates the invariants: no undeclared memory access, no undeclared DMA, no unowned interrupt delivery, no unbounded channel traffic. A backend realizes those invariants with its own mechanisms (page tables / IOMMU / interrupt controllers on Xen; partition configuration on XtratuM; hardware guard bands such as WorldGuard on HPSC).

Warning

No “interference-free” claims The M0 baseline explicitly forbids claiming complete freedom from interference. What the architecture does claim is that interference has measured, contractual boundaries, and that those boundaries must be measured, not asserted (see Interference validation and Research problems).

Isolation and assurance

Determining which isolation properties can remain invariant across x86-64

Xen, NG-ULTRA + XNG/XtratuM, and HPSC + hardware partitioning is Research Problem 1, portable partition semantics. That question, not the existence of any given mechanism, motivates the contract: the contract is what makes difference-based reasoning between targets possible.